firmware: add handler for static layout

Add static layout handler.

Change-Id: I5c4cfe9782d59d32b16556e1d82b468c119eeb76
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/image_handler.hpp b/image_handler.hpp
index e4589f5..f09e7a2 100644
--- a/image_handler.hpp
+++ b/image_handler.hpp
@@ -1,5 +1,9 @@
 #pragma once
 
+#include <functional>
+#include <memory>
+#include <string>
+
 namespace blobs
 {
 
@@ -14,9 +18,16 @@
     /**
      * open the firmware update mechanism.
      *
+     * @param[in] path - the path passed to the handler (the blob_id).
      * @return bool - returns true on success.
      */
-    virtual bool open() = 0;
+    virtual bool open(const std::string& path) = 0;
+};
+
+struct HandlerPack
+{
+    std::string blobName;
+    ImageHandlerInterface* handler;
 };
 
 } // namespace blobs